Passing value in IEnumerable method

Passing value in IEnumerable method

net mvc c#.I have created model for view.I can receive all rows from the
table but when I try to pass value in method which is return list is not
working Here is my code
Controller class
public ActionResult Index()
{
TechnicianDBO db = new TechnicianDBO();
List<Technician> technicians = db.technicians.ToList();
return View(technicians);
}
[HttpPost]
public ActionResult Index(int Postcode)
{
TechnicianDBO db = new TechnicianDBO();
List<Technician> technicians =
db.Jobtechnicians(Postcode).ToList();
return View(technicians);
}
Db class
public IEnumerable<Technician> Jobtechnicians(int postcode)
{
string connectionString =
ConfigurationManager.ConnectionStrings["testConnect"].ConnectionString;
List<Technician> Jobtechnicians = new List<Technician>();
using (SqlConnection con = new
SqlConnection(connectionString))
{
SqlCommand cmd = new
SqlCommand("spGetTechnicianByPostcode", con);
con.Open();
SqlParameter paramId = new SqlParameter();
paramId.ParameterName = "@postcode";
paramId.Value =postcode;
cmd.Parameters.Add(paramId);
SqlDataReader dr = cmd.ExecuteReader();
while (dr.Read())
{
Technician technician = new Technician();
technician.Id = Convert.ToInt32(dr["techId"]);
// technician.Username =
dr["techUsername"].ToString();
technician.Firstname =
dr["techFirstname"].ToString();
technician.Lastname = dr["techLastname"].ToString();
technician.LandlineNo = dr["landlineNo"].ToString();
technician.MobileNo = dr["mobileNo"].ToString();
technician.Address1 = dr["address1"].ToString();
technician.Address2 = dr["address2"].ToString();
technician.Postcode =
Convert.ToInt32(dr["postcode"]);
technician.Email = dr["email"].ToString();
technician.Fax = dr["fax"].ToString();
technician.Profession =
Convert.ToInt32(dr["ProfessionId"]);
Jobtechnicians.Add(technician);
}
return Jobtechnicians;
}